It appears that Google didn't admit there is such.
But to be safe, is always good to maintain quality site.
Here are several important things to keep in mind:
Duplicate content and redundant articles are a no-no.
Avoid creating thin content.
Prioritize user experience. For example, too many ads on your site can create a negative visitor experience and have an undesired impact on your rankings.
Your content should be trustworthy. Visitors that land on your site should feel comfortable giving you their credit card information.
Are you exercising quality control with your content? Your articles should be free of spelling and factual errors.
Are you striving to give your target users an in-depth look into the subject matter? Does your content meet their needs?
This is just a quick overview of what Google expects from you as a content creator. From a user experience perspective, it makes a lot of sense. SOURCE